Osteoporosis influences the health of the females who are in menopause phase. The techniques to detect the markers of bone turnover is very important for preventing osteoporosis. ELISA was developed for detection of urinary N-telopeptide (NTx) as an osteoporosis marker. Our aim is to develop a sensitive method to detect NTx excretion using surface plasmon resonance (SPR). Samples collected were assayed and results suggest that our SPR-based method is promising for monitoring bone loss.